See a list of possible causes in order from the most common to the least.

Kidney stones are solid masses of crystalized calcium or other substances that originate in the kidneys but can pass through the urinary tract. The greatest risk factor is making less than one liter of urine per day.

Obstructive uropathy is a condition in which your urine flow is blocked, and backs up into the kidneys. IIt may be caused by a blockage in one of the ureters - the tube that channels urine between the bladder and th...

Bladder stones are crystals that form when concentrated urine is left in the bladder after urination, often due to dehydration or being unable to empty the bladder totally. Symptoms include painful urination and others.

Obstructive uropathy is a blockage that prevents urine from leaving your kidneys. When this condition develops suddenly and only affects one kidney, it’s called acute unilateral obstructive uropathy. The blockag...

This condition is considered a medical emergency. Urgent care may be required.

An ABO incompatibility reaction can occur if you're given the wrong type of blood during a transfusion. It is a rare but dangerous response by your immune system to the blood. Symptoms include fever, aches, and more.

Preeclampsia is a condition in which a pregnant women has high blood pressure and protein in her urine after the 20th week of pregnancy. Abnormal swelling of the face and hands can be a sign of preeclampsia.

Infective endocarditis is an infection of the heart, normally caused by bacteria in the blood stream. It is a serious medical condition. If left untreated, the infection can damage your heart and may even cause death.

This condition is considered a medical emergency. Urgent care may be required.

Necrotizing vasculitis is the inflammation of blood vessel walls. It can interrupt blood flow, causing skin, muscle, and blood vessel damage, and death of tissues and organs. Its symptoms can affect the entire body.

Sickle cell anemia is a genetic disease that causes red blood cells to have an abnormal shape, causing blood flow problems. This can lead to tissue damage and pain, as well as enlarged spleen, anemia, and other symptoms.

Aspergillosis is an infection, allergic reaction, or fungal growth caused by the Aspergillus fungus. The fungus usually grows on decaying vegetation and dead leaves. Being exposed to the fungus does not necessarily mea...

Polyarteritis nodosa (PAN) is a condition that causes swollen arteries. It primarily affects small and medium-sized arteries, which can become inflamed or damaged. This is a serious disease of the blood vessels cause...

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